The present invention relates to a fuel injector.
More specifically, the present invention relates to a fuel injector for an internal combustion engine, to which the following description refers purely by way of example.
A known internal combustion engine fuel injector comprises an injector body housing a fuel metering valve; and a fitting for connecting the injector body to a high-pressure fuel supply conduit. A known injector body is elongated and tubular in shape, extends along a given axis, and is integral with the fitting connecting the body to the high-pressure fuel supply conduit; and the fitting is located along a lateral wall of, and projects radially with respect to, the injector body. The injector body and fitting are formed from a single rough piece of metal which is hot forged to form an elongated semifinished part having a laterally-extending portion imparting an symmetrical shape to the semifinished part. The asymmetrical semifinished part is then machined to define the injector body and the fitting according to given design parameters, and in particular according to given dimensions, tolerances and surface finish.
Known injectors are expensive to produce on account of the type and number of mechanical operations involved in producing the injector body and fitting, and of which forging is especially expensive and difficult to implement in a continuous-flow system.
It is an object of the present invention to provide an injector which can be produced using a production method which is much cheaper than those of known injectors, but which at the same time provides for at least the same quality standard.
According to the present invention, there is provided a fuel injector comprising an injector body connectable to a high-pressure fuel supply conduit, and a fitting for connecting said supply conduit to said injector body; the injector being characterized in that said injector body and said fitting are separate elements of said injector and connected to each other.
Such an injector provides not only for eliminating high-cost forging, but also for simplifying machining, on account of the injector body being symmetrical and so adapting better to automatic handling and practically any type of machining operation.
In a preferred embodiment of the invention, the injector body is machined from a bar.
This solution is especially advantageous by the semifinished part being formed from a bar, so that forging is replaced by a cutting operation which is easily implemented in a continuous-flow system. Moreover, the semifinished part, like the injector body, is already symmetrical.
The present invention also relates to a method of producing the injector according to the present invention.
According to the present invention, there is provided a method of producing a fuel injector, characterized by cutting off a bar a cylindrical semifinished part to form the injector body.
In a preferred embodiment of the method according to the present invention, an end portion of the supply conduit is deformed between the injector body and the fitting.
This solution is especially advantageous by not requiring that the fitting be fixed hermetically to the injector body, in that the fitting provides for gripping and deforming the end portion of the supply conduit between itself and the injector body to form a hermetic seal between the injector body and the supply conduit. Hermetic sealing is ensured by deformation of the end portion of the supply conduit gripped between the injector body and the fitting.